// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at

//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ESP_MDNS_H_
#define ESP_MDNS_H_

#include <tcpip_adapter.h>
#include "esp_event.h"

#ifdef __cplusplus
extern "C" {
#endif

#define MDNS_TYPE_A                 0x0001
#define MDNS_TYPE_PTR               0x000C
#define MDNS_TYPE_TXT               0x0010
#define MDNS_TYPE_AAAA              0x001C
#define MDNS_TYPE_SRV               0x0021
#define MDNS_TYPE_OPT               0x0029
#define MDNS_TYPE_NSEC              0x002F
#define MDNS_TYPE_ANY               0x00FF

/**
    @brief   mDNS enum to specify the ip_protocol type
*/
typedef enum {
    MDNS_IP_PROTOCOL_V4,
    MDNS_IP_PROTOCOL_V6,
    MDNS_IP_PROTOCOL_MAX
} mdns_ip_protocol_t;

/**
    @brief   mDNS basic text item structure
            Used in mdns_service_add()
*/
typedef struct {
    char* key;                              /*!< item key name */
    char* value;                            /*!< item value string */
} mdns_txt_item_t;

/**
    @brief   mDNS query linked list IP item
*/
typedef struct mdns_ip_addr_s {
    ip_addr_t addr;                         /*!< IP address */
    struct mdns_ip_addr_s* next;            /*!< next IP, or NULL for the last IP in the list */
} mdns_ip_addr_t;

/**
    @brief   mDNS query result structure
*/
typedef struct mdns_result_s {
    struct mdns_result_s* next;             /*!< next result, or NULL for the last result in the list */

    tcpip_adapter_if_t tcpip_if;            /*!< interface on which the result came (AP/STA/ETH) */
    mdns_ip_protocol_t ip_protocol;         /*!< ip_protocol type of the interface (v4/v6) */
    // PTR
    char* instance_name;                    /*!< instance name */
    // SRV
    char* hostname;                         /*!< hostname */
    uint16_t port;                          /*!< service port */
    // TXT
    mdns_txt_item_t* txt;                   /*!< txt record */
    size_t txt_count;                       /*!< number of txt items */
    // A and AAAA
    mdns_ip_addr_t* addr;                   /*!< linked list of IP addreses found */
} mdns_result_t;

/**
    @brief  Initialize mDNS on given interface

    @return
       - ESP_OK on success
       - ESP_ERR_INVALID_ARG when bad tcpip_if is given
       - ESP_ERR_INVALID_STATE when the network returned error
       - ESP_ERR_NO_MEM on memory error
       - ESP_ERR_WIFI_NOT_INIT when WiFi is not initialized by eps_wifi_init
*/
esp_err_t mdns_init();

/**
    @brief  Stop and free mDNS server

*/
void mdns_free();

/**
    @brief  Set the hostname for mDNS server
           required if you want to advertise services

    @param  hostname     Hostname to set

    @return
       - ESP_OK success
       - ESP_ERR_INVALID_ARG Parameter error
       - ESP_ERR_NO_MEM memory error
*/
esp_err_t mdns_hostname_set(const char* hostname);

/**
    @brief  Set the default instance name for mDNS server

    @param  instance_name     Instance name to set

    @return
       - ESP_OK success
       - ESP_ERR_INVALID_ARG Parameter error
       - ESP_ERR_NO_MEM memory error
*/
esp_err_t mdns_instance_name_set(const char* instance_name);

/**
    @brief  Add service to mDNS server

    @param  instance_name    instance name to set. If NULL,
                            global instance name or hostname will be used
    @param  service_type     service type (_http, _ftp, etc)
    @param  proto            service protocol (_tcp, _udp)
    @param  port             service port
    @param  num_items        number of items in TXT data
    @param  txt              string array of TXT data (eg. {{"var","val"},{"other","2"}})

    @return
       - ESP_OK success
       - ESP_ERR_INVALID_ARG Parameter error
       - ESP_ERR_NO_MEM memory error
*/
esp_err_t mdns_service_add(const char* instance_name, const char* service_type, const char* proto, uint16_t port,
                           mdns_txt_item_t txt[], size_t num_items);

/**
    @brief  Remove service from mDNS server

    @param  service_type service type (_http, _ftp, etc)
    @param  proto        service protocol (_tcp, _udp)

    @return
       - ESP_OK success
       - ESP_ERR_INVALID_ARG Parameter error
       - ESP_ERR_NOT_FOUND Service not found
       - ESP_FAIL unknown error
*/
esp_err_t mdns_service_remove(const char* service_type, const char* proto);

/**
    @brief  Set instance name for service

    @param  service_type     service type (_http, _ftp, etc)
    @param  proto            service protocol (_tcp, _udp)
    @param  instance_name    instance name to set

    @return
       - ESP_OK success
       - ESP_ERR_INVALID_ARG Parameter error
       - ESP_ERR_NOT_FOUND Service not found
       - ESP_ERR_NO_MEM memory error
*/
esp_err_t mdns_service_instance_name_set(const char* service_type, const char* proto, const char* instance_name);

/**
    @brief  Set/Add TXT item for service TXT record

    @param  service_type service type (_http, _ftp, etc)
    @param  proto        service protocol (_tcp, _udp)
    @param  key          the key that you want to add/update
    @param  value        the new value of the key

    @return
       - ESP_OK success
       - ESP_ERR_INVALID_ARG Parameter error
       - ESP_ERR_NOT_FOUND Service not found
       - ESP_ERR_NO_MEM memory error
*/
esp_err_t mdns_service_txt_item_set(const char* service_type, const char* proto, const char* key, const char* value);

/**
    @brief  Free query results

    @param  results      linked list of results to be freed
*/
void mdns_query_results_free(mdns_result_t* results);

/**
    @brief  Query mDNS for service

    @param  service_type service type (_http, _arduino, _ftp etc.)
    @param  proto        service protocol (_tcp, _udp, etc.)
    @param  timeout      time in milliseconds to wait for answer.
    @param  max_results  maximum results to be collected
    @param  results      pointer to the results of the query

    @return
       - ESP_OK success
       - ESP_ERR_INVALID_STATE  mDNS is not running
       - ESP_ERR_NO_MEM         memory error
       - ESP_ERR_INVALID_ARG    parameter error
*/
esp_err_t mdns_query_ptr(const char* service_type, const char* proto, uint32_t timeout, size_t max_results,
                         mdns_result_t** results);

/**
    @brief  Query mDNS for TXT record

    @param  instance_name    service instance name
    @param  service_type     service type (_http, _arduino, _ftp etc.)
    @param  proto            service protocol (_tcp, _udp, etc.)
    @param  timeout          time in milliseconds to wait for answer.
    @param  result           pointer to the result of the query

    @return
       - ESP_OK success
       - ESP_ERR_INVALID_STATE  mDNS is not running
       - ESP_ERR_NO_MEM         memory error
       - ESP_ERR_INVALID_ARG    parameter error
*/
esp_err_t mdns_query_txt(const char* instance_name, const char* service_type, const char* proto, uint32_t timeout,
                         mdns_result_t** result);

/**
    @brief  Query mDNS for A record

    @param  host_name    host name to look for
    @param  timeout      time in milliseconds to wait for answer.
    @param  addr         pointer to the resulting IP4 address

    @return
       - ESP_OK success
       - ESP_ERR_INVALID_STATE  mDNS is not running
       - ESP_ERR_NO_MEM         memory error
       - ESP_ERR_INVALID_ARG    parameter error
*/
esp_err_t mdns_query_a(const char* host_name, uint32_t timeout, ip4_addr_t* addr);

/**
    @brief   System event handler
            This method controls the service state on all active interfaces and applications are required
            to call it from the system event handler for normal operation of mDNS service.

    @param  ctx          The system event context
    @param  event        The system event
*/
esp_err_t mdns_handle_system_event(void* ctx, system_event_t* event);

#ifdef __cplusplus
}
#endif

#endif /* ESP_MDNS_H_ */
